Seal cover for conduits



R. F. KRUCKY 2,763,293

Sept. 18, 1956 SEAL COVER FOR connurrs Filed Feb. 15, 1.954

a "m," a?) Unite This invention relates generally to a device for covering and sealing the end of an open conduit, and more specifically to a closure or cover having means for sealing the open end of a well casing, and means for locking the cover on the well casing.

Conduits and pipes of various forms are used in applications in which one end is open or uncovered. A situation in which this occurs is the use of a conduit as a passageway through which a wrench may be inserted to actuate valves of an underground water main. Also, there is a widespread use of well casings for driven wells, particularly in rural and outlying city areas where a community water supply is not available. These are examples of outdoor uses of conduits having an open end, although similar examples of indoor use can. also be cited.

Where a conduit is used having an open end, there exists the problem of providing means for sealing and covering the open end to prevent dirt, insects, rodents, leaves, twigs and other foreign matter from entering the conduit. This is particularly important in the case. of well casings, especially in rural school areas Where the water supply available for consumption by the children is well water. The entrance of rodents, insects and other foreign matter into the water supply might contaminate the water so that it is injurious to the health of the children drinking the water. In the past, covers or closures for outdoor and indoor open conduits have been used with some degree of success. In such prior art covers, however, it is still possible for dirt and-other foreign matter to enter the conduit to a limited extent. Also, such covers are readily removable byunauthorized persons who may tamper with the conduit and introduce foreign matter therein. The nature of the present invention resides in providing a cover or cap for open conduits having an improved means for sealing the open end of the conduit and means for locking the cover to the conduit so that a passerby cannot readily tamper with the conduit or remove the cdver therefrom.

It is therefore an object of the present invention to provide an improved cover having three sealing surfaces, for sealing the open end of a conduit against entry of foreign matter.

Another object of the invention is to provide a conduit cover that has improved means for locking the cover to the conduit so that it is not readily removable therefrom.

Another object of the invention is to provide a cover for an open end of a conduit in which none of the parts comprising the cover can become disengaged therefrom and fall into the casing when the cover is removed.

Another object of the invention is to provide a cover for an open end of a conduit that has fewer parts and is more economical than prior known covers.

Objects and advantages other than those set forth above will be apparent from the following description when read in connection with the accompanying drawing, in which:

2,763,293 Patented Sept. 18, 1956 Fig. 1 is a plan view of a cover embodying the invention;

Fig. 2 is an elevation view in section of a cover in an unsealed and unlocked position embodying the invention taken along line 1I--II of Fig. 1;

Fig. 3 is an elevation view in section of a cover in a sealing and locking position embodying the invention; and

Fig. 4 is a plan view of a nut used in practicing the invention.

Referring to the drawing, this invention is illustrated as applied to a closure shown as a cover 5 for sealing the open end of a conduit shown as a well casing 6, and being locked thereto. The cover 5 comprises a cap, resilient sealing members 8, 9, a nut, a bolt 11 and a cotter key 12.

The cap consists of an annular plate 13 having a pcripheral depending flange 14. The plate 13 defines an opening 15 at the center thereof through whichthe bolt 11 may pass. The cap can be made of any material such as cast iron, but since it is used in many outdoor applications, it should preferably be constructed of a rust resisting metal such as aluminum or an aluminum alloy. The flange 14 defines a tapped opening 16 through which a set screw 17, preferably an Allen screw actuable by an Allen wrench, may be threaded to engage the outer wall or surface of the well casing 6. Although only one tapped opening 16 is shown, a plurality of such openings may be used spaced circumferentially around the. flange 14.

The plate 13 and flange 14 of the cap cooperate to define a cavity. Within this cavity is silient sealing member 8 with one side of the sealing member adjacent one side of the plate 13. Sealing member 8 is annular having an outer diameter less than the inner diameter of flange 1d, and preferably equal to or greater than the outer diameter of the well casing 6. The clearance between the outer surface 18 of the sealing members and the inner surface 19 of the flange 14 should be suflicient to allow the sealing member 8 in an uncompressed state to fit within the cavity formed by the plate 13 and flange 14 without buckling. The sealing member 8 contacts the annular end portion 20 of the well casing 6 when the cover 5 is placed upon the well casing 6. The sealing member 5 defines an opening through the center thereof in register with the opening 15 through which the bolt 11 may pass.

The sealing member 9 is annular in form having an opening centrally disposed therein. Sealing member 9 further has an outer diameter less than the inner diameter of the well casing 6 so that the sealing member 9 may be positioned within the well casing 6. The clearance between the outer surface 21 ofthe sealing member 9 and the innersurface 22 of the well'casing should be sufficient to allow the sealing member 9, in an uncompressed state, to enter the well casing 6 without binding. Although the sealing member 9 in Fig. 2 is shown with its outer surface 21 engaging the inner surface22 of; the

'well casing in its uncompressed state, it is preferably to provide a clearance therebetween.

The sealing members 3, 9 may be made of any resili'ent material such as rubber or any synthetic composition having resilient properties. Although the sealing members 8, 9 are shown as individual members in Figs. 2 and 3, they may be replaced by a single resilient element having the combined shape and form of resilient sealing members 8, 9. Also, the cover 5 W0 ld function properly, but not as satisfactory, by using sealing member 9 only and omitting sealing member 8 entirely.

The nut comprises an annular disk 23 having an annular boss 24 on each side of the disk 23 at the center thereof. The disk need not be confined to an annular shape, but may be any other shape such as square or positioned the rehexagonal. The nut defines a threaded opening 25 through the center of the disk 23 and boss 24. On the opposite side, the disk 23 defines a plurality of radial ribs 26 extending radially from the boss 24 to the periphery ofthe disk 23. Although a plurality of ribs 26 are shown, only one rib would be suflicient. Also, the ribs 26 need not extend radially for the entire radial width of the disk 23. The nut may be constructed of any suitable metal, although for usage in well casings, a nonrusting metal such as aluminum is preferable.

The parts comprising the cover are held together by the bolt 11. The bolt 11, preferably constructed of a non-rusting metal, has a threaded portion 27 having an opening 28 passing diametrically therethrough. To assemble the cover 5, the bolt 11 is inserted through the opening of the plate 13, the opening of the scaling member 8, the opening of the sealing member 9 and into threaded engagement with the threaded opening of the disk 23. The disk 23 and sealing member 9 are prevented from falling off of the threaded portion 27 of the bolt 11 and into the well casing 6 by means of the cotter key 12 inserted in the opening 28. Although applicant prefers to use the cotter key 12 insertable in the opening 28, any other means could be used to prevent the disk and sealing member 9 from falling into the well casing 6.

Although the cover 5 is shown as having only one opening passing through the center accommodating the bolt 11, the invention is equally applicable to covers having a plurality of openings and bolts passing through the cover. Where a plurality of openings and bolts are used, it is not necessary to have the disk 23 provided with the ribs 26 to hold the nut from turning when the bolts are turned.

In operation, the cover 5, with the sealing members 8, 9 in an uncompressed state, is positioned on a well casing 6 or any other conduit as shown in Fig. 2. To lock the cover 5 to the well casing 6, the set screw 17 is inserted into the tapped opening 16 and turned until the tip of the set screw 17 firmly engages the outer wall of the well casing 6. An Allen screw is preferably used so that removability of the cover after locking is very difficult without an Allen wrench. This discourages tampering with and removal of the cover by unauthorized persons. To seal the cover 5 to the well casing 6, the bolt 11 is turned in the proper tance between the nut and the plate 13. The ribs 26 of the disk 23 of the nut become embedded into the sealing member 9 as the bolt 11 is turned thereby preventing the nut from turning as the bolt is turned. Decreasing this axial distance subjects the sealing members 8, 9 to a compressive force. The resilient material of the sealing is forced into sealing engagement with the inner surface 22 of the well casing 6, and the outer surface 18 of sealing member 8 is forced into sealing engagement with the inner surface 19 of the bolt 11 causes the pordirection to decrease the axial dis- Although but one embodiment has been illustrated and 1 described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

It is claimed and desired to secure by Letters Patent:

1. A closure of a permanent nature for a conduit eoman annular flange adapted to fit over the open end of said conduit; screws threadedly carprising: a cap having ried by said flange for releasably securing said cap to said conduit; a resilient sealing member having a first circular portion of a lesser diameter than the inner diameter of said conduit, and a second circular portion of a lesser diameter than the inner diameter of said flange and a greater diameter than the inner diameter of said conduit, said second portion having one entire side thereof disposed against said cap; a disk-like nut having one entire side disposed against the outer face of said first circular portion, said nut being disposed within said conduit and having a radially extending rib along said one side; said cap and said sealing member each having a central axial opening therethrough; and a bolt passed through said openings and threadedly engaging said nut whereby said sealing member may be compressed between said cap and said nut.

2. A closure of a permanent nature for a conduit comprising: a cap having an annular flange adapted to fit remove said closure from said conduit.

References Cited in the file of this patent UNITED STATES PATENTS 

